Peroxidase will be isolated from earthworms, isopods, millipedes and slugs. An affinity chromatography procedure will be developed. The enzyme will be assayed for deaminase activity and microbicidal action. In histological work the cytological locus of the enzyme will be determined through electron microscopy. The isolated enzymes will be characterized in terms of molecular weight, Michaelis constant, and pH optima for deamination and microbicidal action.